A 28-year-old man with no prior psychiatric history presents with acute-onset chorea, compulsive behaviors, and emotional lability three weeks after group A streptococcal pharyngitis. Vital signs: BP 118/76, HR 92, RR 16, Temp 37.2°C, SpO2 98%. Laboratory studies show elevated anti-DNase B titers. Echocardiography reveals no valvular disease. He denies recent cocaine use. Which pathophysiologic mechanism best explains his neuropsychiatric syndrome?

  1. A)Dopamine depletion from streptococcal toxins
  2. B)Autoimmune demyelination of motor tracts
  3. C)Viral reactivation in the substantia nigra
  4. D)Direct bacterial invasion of the striatum
  5. E)Molecular mimicry causing anti-basal ganglia antibodiesGABARITO

Explicação

Sydenham chorea is part of acute rheumatic fever, caused by molecular mimicry where streptococcal antigens cross-react with basal ganglia epitopes, triggering anti-basal ganglia antibodies. This causes chorea and behavioral changes. PANDAS (pediatric autoimmun... Ver explicação completa e trilha adaptativa →

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